What is an SLA?

A service level agreement (SLA) is the part of a service contract that sets measurable targets, such as how quickly the provider will respond to and resolve an issue. In IT support, the two most common are first response time and resolution time, usually set by ticket priority.

First response and resolution

  • First response time runs from when a ticket is created to when a technician first replies or starts work. An automatic "we got your ticket" email usually doesn't count.
  • Resolution time runs from creation until the issue is fixed and the ticket is closed.

The contract should say whether targets run in business hours or around the clock, and whether the clock pauses while the provider is waiting on the client.

SLA attainment % = tickets that met the target / tickets measured × 100

Worked example

PriorityFirst responseResolution
P1: business down1 hour4 hours
P2: a team affected4 business hours1 business day
P3: one user, workaround exists8 business hours3 business days

In October a client logged 40 tickets. 38 got a first response within target: 38 / 40 = 95%. 36 were resolved within target: 36 / 40 = 90%. The monthly report shows both numbers and explains the four resolution misses.

Common mistakes

  • Counting auto-replies as first response. It makes every ticket look instant.
  • Mixing business and calendar hours across clients or months.
  • Not pausing the clock when waiting on the client, or pausing it too freely.
  • Reporting averages only. An average response of 40 minutes can hide one P1 that waited three hours.
  • Wrong priorities. If tickets are logged at the wrong priority, every SLA figure is off.

Related terms

  • QBR (quarterly business review): A quarterly business review (QBR) is a meeting a service provider holds with each client every quarter to review results against agreed targets, discuss risks and plan the next quarter.
  • Month over month (MoM): Month over month (MoM) compares a figure for one month with the same figure for the month before, as a dollar change and a percentage change.

Further reading